Anything that would help getting the more laymen users to use other clients beside the satoshi client is a plus IMHO because I have this sneaky suspicion a lot of people get turned off once they start waiting for the blockchain to download. Of course I can't substantiate this suspicion with any evidence.
I would have this strong suspicion as well. Having users download the application without telling them well in advance that they'll need to wait till tomorrow to use it suggests to them that we're out of touch with their need for their money to be convenient and usable in a rapid fashion like cash, paypal, and credit cards. I know lots of people who would love to own some bitcoins if only they knew how to get in and out of them easily and how to trade them (and you can bet not very many people are saying "download the client from bitcoin.org" to any of them).
I would love to know where you are getting credit cards faster than you can download the blockchain.